ICA angioplasty with cerebral protection

ABSTRACT

A method of performing an operation including angioplasty of the internal carotid artery includes blocking blood flow in the internal carotid artery, performing the angioplasty while the blood flow is blocked in the internal carotid artery, and reversing flow in the internal carotid artery after the angioplasty has been performed to wash material loosened during the angioplasty out of the internal carotid artery. Normal flow in the internal carotid artery is restored after the loosened material is washed out of the internal carotid artery.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of my U.S. Provisional Patent Application Ser. Nos. 60/038,040; 60/037,226; 60/037,225; and 60/038,039, all filed Feb. 5, 1997 and all incorporated herein by reference. This application also claims priority of my U.S. Provisional Patent Application also filed on Feb. 6, 1997 with the four above-mentioned provisional patent applications and entitled “ICA ANGIOPLASTY WITH CEREBRAL PROTECTION” and bearing attorney docket number V97004US (16064/4). That application is also incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable

REFERENCE TO A “MICROFICHE APPENDIX”

[0003] Not applicable

BACKGROUND OF THE INVENTION

[0004] 1. Field of the Invention

[0005] The present invention relates to internal carotid artery (ICA) angioplasty with cerebral protection. More particularly, the present invention relates to a system for conducting angioplasty while minimizing risk of strokes.

[0006] 2. General Background of the Invention

[0007] When angioplasties are performed, sometimes plaque gets dislodged and travels into the brain, sometimes causing strokes.

[0008] The following references are hereby incorporated by reference: U.S. Pat. Nos. 3,726,269; 4,033,331; 4,169,464; 4,573,966; 4,925,445; 4,935,017; 5,120,323; 5,163,906; 5,199,951; 5,203,776; 5,215,540; 5,219,355; 5,267,982; 5,290,229; 5,304,131; 5,342,306; 5,348,545; 5,368,566; 5,389,090; 5,458,574; 5,462,529; 5,480,380; 5,484,412; European Patent Specification Publication Nos. 0 339 799 B1 and 0 277 366 A1 and PCT International Application Publication No. WO 96/26758.

BRIEF SUMMARY OF THE INVENTION

[0009] The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner. What is provided is a method of performing an operation including angioplasty of the internal carotid artery comprising the following steps: (a) blocking blood flow in the internal carotid artery; (b) performing the angioplasty while the blood flow is blocked in the internal carotid artery; (c) reversing flow in the internal carotid artery after the angioplasty has been performed to wash material loosened during the angioplasty out of the internal carotid artery; and (d) restoring normal flow in the internal carotid artery.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0010] For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:

[0011] In FIG. 1 initial placement of the flow control guide catheter 111 has been made, but the balloon 118 has not been inflated; antegrade flow is still present in the common carotid artery 61 and internal and external carotid arteries 71, 72.

[0012] In FIG. 2, inflation of the guide catheter balloon 118 stops flow in the common carotid artery 61 and reverses flow in the internal carotid artery 71. The high pressure intracranial vascular system will supply the low pressure sump of the external carotid artery 72.

[0013] In FIG. 3, while flow reversal is occurring, a soft tipped “wire with a balloon” 80 is advanced safely through the lesion 40; any material displaced during passage will flow in a retrograde course out the external carotid artery 72.

[0014] In FIG. 4, the distal balloon 91 is inflated, stopping all flow in the internal carotid artery 71.

[0015] In FIG. 5, the guide catheter balloon 111 is deflated, washing out the stagnant blood and debris in the region of the stenosis 40.

[0016] In FIG. 6, both balloons 81, 118 are inflated and the angioplasty catheter 90 is delivered safely to its intended location.

[0017] In FIG. 7, the angioplasty is performed while flow is arrested in the common carotid 61 and internal carotid 71 arteries.

[0018] In FIG. 8, after initial angioplasty, a stent 50 is delivered into the closed system, again with both the distal and proximal flow occluded.

[0019] In FIG. 9, the stent 50 is safely deployed under flow arrest.

[0020] In FIG. 10, the angioplasty catheter 90 is withdrawn, leaving the stent 50 in place with flow arrested in the carotid arteries 61, 71, 72.

[0021] In FIG. 11, the distal balloon 81 is deflated, allowing reversal of flow again in the internal carotid artery 71. This allows any retained material to be washed into the external carotid artery 72 again.

[0022] In FIG. 12, the distal balloon 81 is re-inflated, again stopping flow in the internal carotid artery 71.

[0023] In FIG. 13, the proximal balloon 118 is deflated. This allows high pressure antegrade flow into the external carotid artery 72 and allows contrast injection through the inner lumen of the guide catheter 111. Evaluation of the result of the angioplasty/stent is now possible. Any retained material is now forcefully washed out of the system into the external carotid artery 72.

[0024] In FIG. 14, the proximal balloon 118 is again inflated.

[0025] In FIG. 15, the distal balloon 81 is deflated. While flow is again reversed in the internal carotid artery 71, the distal wire/balloon 80 is safely withdrawn, again with no chance of dislodging any material into the intracranial flow.

[0026] In FIG. 16, once the inner wire/balloon 80 has been withdrawn, the guide catheter balloon 118 is deflated, allowing final contrast injection through the guide catheter lumen to evaluate the results.

DETAILED DESCRIPTION OF THE INVENTION

[0027] This is also the technique of choice for internal carotid artery stenting due to its excellent cerebral protection.

[0028] 1. Select the common carotid artery 61 using a selective diagnostic cerebral catheter; evaluate the path available to the angioplasty site.

[0029] 2. Exchange the diagnostic catheter for a flow control guide catheter utilizing a safe “neuro” exchange wire.

[0030] (Instead of the first two steps listed above, one could instead use the flow control guide catheter 111 of the present invention which is a modified version of the guide catheter disclosed in the attached provisional patent application entitled “Guide Catheter System”, which modified version is discussed below).

[0031] 3. Inflate the balloon 118 on the flow control catheter 111, occluding flow in the common carotid artery 61 and resulting in reversal of flow in the internal carotid artery 71 or cessation of flow (at the very least).

[0032] 4. Load a micro-occlusion balloon catheter 80 containing a microwire through the selected angioplasty balloon catheter 90. (This will necessitate the placement of a microballoon on a microcatheter after loading, or the use of a proprietary device, currently in development.) Carefully navigate the micro-occlusion balloon 81 past the stenosis 40 with the angioplasty balloon 91 remaining proximal within the guide catheter lumen. The occluded common carotid artery 61 thus protects this initial dangerous crossing.

[0033] 5. Before inflating the distal balloon 81, aspirate through the guide catheter 111 to remove any debris dislodged during the initial crossing of the plaque 40; any remainder will flow in a retrograde direction into the external carotid artery 72.

[0034] 6. Inflate the distal micro-occlusion balloon 81, stopping all flow in the internal carotid artery 71.

[0035] 7. Deflate the guide catheter occlusion balloon 118; this now allows the previously stagnant blood in the common carotid artery 61 to wash out into the external carotid artery 72 and refreshes this territory. It also further washes out the potentially disturbed stenotic region, with debris again going into the external carotid artery 72.

[0036] 8. Reinflate the guide catheter occlusion balloon 118, ceasing flow in the common carotid artery 61.

[0037] 9. Advance the angioplasty catheter 90 over the wire/micro-occlusion balloon 80 into place and perform the angioplasty (and stent placement, if applicable).

[0038] 10. Deflate the angioplasty balloon 91 and withdraw this catheter 90.

[0039] 11. Slowly infuse contrast through the guide catheter 111 to visualize the angioplasty site.

[0040] 12. Repeat if necessary (and place stent if necessary).

[0041] 13. Open the external lumen of the guide catheter 111 to the air.

[0042] 14. Deflate the distal occlusion balloon 81 and let backbleeding occur for a few seconds, both into the external carotid artery 72 and out the guide catheter 111.

[0043] 15. Close the external drainage of the guide catheter 111; let the retrograde flow from the internal carotid artery 71 continue into the external carotid artery 72. Perfuse with ReoPro, etc., as indicated.

[0044] 16. Perform repeat angiogram to evaluate the status of the angioplasty site by injecting through the guide catheter lumen, slowly.

[0045] 17. Remove all indwelling catheters/balloons except for the guide catheter 111.

[0046] 18. Deflate the guide catheter balloon 118 and perform final angioplasty site evaluation.

[0047] 19. Perform final evaluation of intracranial cerebral vasculature.

[0048] The preferred guide catheter system for getting the balloon catheter 111 to its intended location is the guide catheter system disclosed in the attached U.S. Provisional Patent Application Ser. No. 60/037,225 entitled “Guide Catheter System”, but modified to include a balloon 118 on the guide catheter 111 disclosed herein. Thus, one could use the system disclosed therein, replacing the catheter 11 disclosed therein with balloon catheter 111, which is the same as catheter 11 except that catheter 111 also includes a balloon 118 and means for inflating and deflating balloon 118.

[0049] Parts list

[0050]40 stenosis

[0051]50 stent (made of stainless steel and could be, e.g., a stent commercially available from Palmaz)

[0052]61 selected vessel (common carotic artery)

[0053]62 intended location of tip 112 of catheter 111

[0054]71 internal carotid artery

[0055]72 external carotid artery

[0056]80 wire with balloon (e.g., a wire with balloon commercially available from Johnson & Johnson as part no. P104)

[0057]81 balloon of wire 80

[0058]90 angioplasty catheter (e.g., a Diamond TM brand angioplasty catheter commercially available from Boston Scientific having a balloon which is 6 mm in diameter by 20 mm long)

[0059]91 balloon of angioplasty catheter

[0060]110 guide catheter system

[0061]111 guide catheter (e.g., a catheter commercially available as FasGuide made by Target Therapeutic)

[0062]112 soft, atraumatic tip of guide catheter 11

[0063]113 very stiff proximal shaft of guide catheter 111

[0064] Enclosed is an appendix with more information about the present invention.

[0065] All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.

[0066] The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. 

1. A method of performing an operation including angioplasty of the internal carotid artery comprising the following steps: (a) blocking blood flow in the internal carotid artery; (b) performing the angioplasty while the blood flow is blocked in the internal carotid artery; (c) reversing flow in the internal carotid artery after the angioplasty has been performed to wash material loosened during the angioplasty out of the internal carotid artery; (d) restoring normal flow in the internal carotid artery.
 2. A method of performing an operation including angioplasty of the internal carotid artery comprising the following steps: (a) blocking flow in the common carotid artery, thus causing retrograde blood flow in the internal carotid artery; (b) blocking flow in the internal carotid artery, distal of the stenosis; (c) performing angioplasty on the stenosis; (d) unblocking flow in the internal carotid artery, thus allowing retrograde blood flow in the internal carotid artery into the external carotid artery; and (e) unblocking flow in the common carotid artery.
 3. Apparatus for performing angioplasty, including: (a) a guide catheter having a first occlusion balloon adjacent a distal end thereof, the first occlusion balloon being sized to stop blood flow in a first artery; (b) a wire which can be advanced through the guide catheter and which includes a second occlusion balloon adjacent a distal end thereof the second occlusion balloon being sized to stop blood flow in a second artery; (c) means for selectively inflating and deflating the first balloon; (d) means for selectively inflating and deflating the second balloon; (e) an angioplasty balloon catheter which can be advanced through the guide catheter and along the wire to the site of a stenosis in the second artery. 